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        <h2>
          <span class="refentrytitle">tempo</span>
        </h2>
        <p>tempo — 
      Apply tempo control to an uninterpreted score.
          </p>
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      <div class="refsect1">
        <a id="idp158050944"></a>
        <h2>Description</h2>
        <p>
      Apply tempo control to an uninterpreted score.
    </p>
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      <div class="refsect1">
        <a id="idp158052288"></a>
        <h2>Syntax</h2>
        <pre class="synopsis"><span class="command"><strong>tempo</strong></span> ktempo, istartempo</pre>
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      <div class="refsect1">
        <a id="idp158054368"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>istartempo</em></span> -- initial tempo (in beats per minute). Typically 60.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp158056128"></a>
        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>ktempo</em></span> -- The tempo to which the score will be adjusted.
    </p>
        <p>
      <span class="emphasis"><em>tempo</em></span> allows the performance speed of Csound scored events to be controlled from within an orchestra. It operates only in the presence of the Csound <a class="link" href="CommandFlags.html#FlagsMinusLowerT"><em class="citetitle">-t</em></a> flag. When that flag is set, scored events will be performed from their uninterpreted p2 and p3 (beat) parameters, initially at the given command-line tempo. When a <span class="emphasis"><em>tempo</em></span> statement is activated in any instrument (<span class="emphasis"><em>ktempo</em></span> 0.), the operating tempo will be adjusted to <span class="emphasis"><em>ktempo</em></span> beats per minute. There may be any number of <span class="emphasis"><em>tempo</em></span> statements in an orchestra, but coincident activation is best avoided.
    </p>
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      <div class="refsect1">
        <a id="idp158062112"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the tempo opcode. Remember, it only works if you use the <a class="link" href="CommandFlags.html#FlagsMinusLowerT"><em class="citetitle">-t</em></a> flag with Csound. The example uses the file <a class="ulink" href="examples/tempo.csd" target="_top"><em class="citetitle">tempo.csd</em></a>.

      </p>
        <div class="example">
          <a id="idp158064944"></a>
          <p class="title">
            <strong>Example 922. Example of the tempo opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
<span class="comment">; Audio out   Audio in</span>
-odac           -iadc    -t60 <span class="comment">;;;RT audio I/O</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o tempo.wav -W -t60 ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="comment">; Initialize the global variables.</span>
<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">kr</span> <span class="op">=</span> 4410
<span class="ohdr">ksmps</span> <span class="op">=</span> 10
<span class="ohdr">nchnls</span> <span class="op">=</span> 1

<span class="comment">; Instrument #1.</span>
<span class="oblock">instr</span> 1
  kval <span class="opc">tempoval</span>

  <span class="opc">printk</span> 0.1, kval

  <span class="comment">; If the fourth p-field is 1, increase the tempo.</span>
  <span class="octrl">if</span> (p4 <span class="op">==</span> 1) <span class="octrl">kgoto</span> <span class="olabel">speedup</span>
    <span class="octrl">kgoto</span> <span class="olabel">playit</span>

<span class="olabel">speedup</span><span class="op">:</span>
  <span class="comment">; Increase the tempo to 150 beats per minute.</span>
  <span class="opc">tempo</span> 150, 60

<span class="olabel">playit</span><span class="op">:</span>

  a1 <span class="opc">oscil</span> 10000, 440, 1
  <span class="opc">out</span> a1
<span class="oblock">endin</span>

<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>

<span class="comment">; Table #1, a sine wave.</span>
<span class="stamnt">f</span> 1 0 16384 10 1

<span class="comment">; p4 = plays at a faster tempo (when p4=1).</span>
<span class="comment">; Play Instrument #1 at the normal tempo, repeat 3 times.</span>
<span class="stamnt">r</span>3
<span class="stamnt">i</span> 1 00.00 00.25 0
<span class="stamnt">i</span> 1 00.25 00.25 0
<span class="stamnt">i</span> 1 00.50 00.25 0
<span class="stamnt">i</span> 1 00.75 00.25 0
<span class="stamnt">s</span>

<span class="comment">; Play Instrument #1 at a faster tempo, repeat 3 times.</span>
<span class="stamnt">r</span>3
<span class="stamnt">i</span> 1 00.00 00.25 1
<span class="stamnt">i</span> 1 00.25 00.25 0
<span class="stamnt">i</span> 1 00.50 00.25 0
<span class="stamnt">i</span> 1 00.75 00.25 0
<span class="stamnt">s</span>

<span class="stamnt">e</span>

<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
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        <p><br class="example-break" />
    </p>
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      <div class="refsect1">
        <a id="idp158069264"></a>
        <h2>See Also</h2>
        <p>
      <a class="link" href="tempoval.html" title="tempoval"><em class="citetitle">tempoval</em></a>
    </p>
      </div>
      <div class="refsect1">
        <a id="idp158071376"></a>
        <h2>Credits</h2>
        <p>Example written by Kevin Conder.</p>
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